Luhman grows sorghum and then allows his cows to graze on the plants. They eat the top portion of the plant while trampling the lower part into the ground.

"We do a planned grazing system using our perennial pastures," he said. While other farmers let their herd in to graze when the plant is about 10 inches, Luhman waits until the plant is nearly 25 inches tall. That means it has deeper roots and more energy put back into the soil.

"So there's more water infiltration, more organic matter and less tillage," he said.

A pound of organic matter — which is about 58 percent carbon — can hold up to six pounds of water in the soil, according to the University of Minnesota Extension.

Luhman said he aims to leave the soil in a better state than when he started.

The Land Stewardship Project hopes to educate farmers about how adding carbon to the soil not only helps battle climate change but can also have economic and agricultural benefits for farmers, said Shona Snater, a member of the project's soil health team.

"We want to promote the positive benefits," she said. "Maybe not just for climate change, but for their own profitability."